Rauner is suspect in the eyes of some Republicans for his ties and campaign contributions to leading Democrats, like Chicago Mayor Rahm Emanuel.

That may have been why his wife, Diana, wasn't often seen with him on the campaign trail leading up to the primary.

"This morning I'm here as a lifelong Democrat ..."

She introduced herself two mornings after the primary. In a general election, Democratic support may be seen as less of a liability, and more of a bipartisan strength.

Diana Rauner joins about two dozen others announcing support for her husband, including a former Democratic state senator, a fundraiser for President Barack Obama, and Newton Minow, who was FCC chairman under President John F. Kennedy.

"President Kennedy once said 'party loyalty asks too much' I think this is one of those times," he said. "I'm a strong Democrat, but I'm taking a leave of absence from my party because Illinois is in desperate shape."

Democratic Gov. Pat Quinn tried to brush off the defectors. He says Rauner, who only got 40 percent of the primary vote, has plenty of work to do winning over Republicans.